Isn't that discrimination against people who are already adapted to life in Canada?
No, it isn't. Can you explain how you arrived at "discrimination"?
To be fair, arent they the better candidates than candidates who hasnt even left their home country before?
Not entirely. "Better" is very subjective. What do you mean by "better" here? What is the context?
Why would OINP favour FSW with fewer Canadian visits/connections over CEC from other provinces? This is absurd.
For instance, you are employed in Vancouver, BC. You have a job there and you apply to OINP for a nomination. All OINP is looking for is a guarantee that you will move to ON if and when a nomination is issued (and you don't use it as a backdoor just to get PR and keep working in BC). The thought process is pretty natural here, isn't it? This guy is employed in BC but has applied for OINP. Why might that be? Since you are already in Canada, they expect you to show some ties to the province, visits etc.
Even FSW applicants are asked for a settlement plan. If you think there is inequality and bias here, it is all in your head.